The subject matter disclosed herein relates to circuit breakers and, more particularly, to a retaining assembly of a circuit breaker contact system.
An electrical switching apparatus, such as a circuit breaker, provides protection for electrical systems from electrical fault conditions such as, for example, current overloads, short circuits, abnormal voltage and other fault conditions. Typically, circuit breakers include a housing and an operating mechanism which opens separable electrical contacts to interrupt the flow of current through the conductors of an electrical system in response to certain fault conditions.
To maintain a breaker withstand current rating, the contacts must be maintained in a closed condition at the current withstand rating. On the other hand, the short circuit let-through current must be capable of opening the contacts quickly during a high short circuit condition. Opening of the contacts during a short circuit event involves movement of a carrier assembly, to which moveable contact arms are coupled, at a velocity that may be sufficient to lead to a rebounding of the carrier assembly subsequent to impact with a stopper terminal. Such a rebound effect presents the possibility of a “restrike” of the contacts, which in turn damages the contacts. Therefore, dampening or eliminating the rebound of the carrier assembly would be advantageous.